Refrigeration cycle apparatus

Patent metadata

Field	Value
Publication number	US-10418915-B2
Application number	US-201515549398-A
Country	US
Kind code	B2
Filing date	Mar 31, 2015
Priority date	Mar 31, 2015
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

A refrigeration cycle apparatus includes: a refrigerant circuit, a use side heat exchanger, a pressure reducing device, and a heat source side heat exchanger; A fan is provided together with at least one, selected from between, the use side heat exchanger and the heat source side heat exchanger and that has a fan motor; a relay unit connected to a direct-current supply device via the direct-current circuit breaker; a resistor unit connected in parallel to the relay unit; a DC/AC converter configured to convert a direct-current voltage supplied from the direct-current supply device via either the relay unit or the resistor unit into an alternating-current voltage and to supply the alternating-current voltage to at least one, selected from between, the compressor motor and the fan motor; and an opening and closing control unit configured to bring the relay unit into an open state when the direct-current circuit breaker becomes open.

First claim

The invention claimed is:

1. A refrigeration cycle apparatus comprising:
a refrigerant circuit structured by sequentially connecting a compressor having a compressor motor, a use side heat exchanger, a pressure reducing valve, and a heat source side heat exchanger, by using a refrigerant pipe;
a fan that is provided together with at least one, selected from between, the use side heat exchanger and the heat source side heat exchanger and that has a fan motor;
a relay unit connected to a direct-current supply device via a direct-current circuit breaker;
a resistor unit connected in parallel to the relay unit;
a DC/AC converter configured to convert a direct-current voltage supplied from the direct-current supply device via either the relay unit or the resistor unit into an alternating-current voltage and to supply the alternating-current voltage to at least one, selected from between, the compressor motor and the fan motor;
a smoothing capacitor connected to an input terminal of the DC/AC converter and configured to smooth the direct-current voltage input thereto from the direct-current supply device, and
a controller configured to bring the relay unit into an open state when the direct-current circuit breaker becomes open, wherein
the direct-current supply device includes a battery, and
the controller is configured to bring the relay unit into a closed state when a voltage of the smoothing capacitor has increased to a switch reference voltage, the switch reference voltage being set based on a voltage of the battery.

2. The refrigeration cycle apparatus of claim 1 , wherein
the controller is configured to bring the relay unit into the open state when receiving an input of an open signal being output from the direct-current circuit breaker and indicating that the direct-current circuit breaker is open.

3. The refrigeration cycle apparatus of claim 2 , wherein
the open signal is output from the direct-current circuit breaker via the direct-current supply device.

4. The refrigeration cycle apparatus of claim 1 , wherein
the controller brings the relay unit into the open state when a voltage of the smoothing capacitor becomes lower than a reference voltage set in advance.

5. The refrigeration cycle apparatus of claim 1 , wherein
the controller brings the relay unit into the open state when a voltage difference between an output voltage of the battery and a voltage of the smoothing capacitor exceeds a threshold voltage set in advance.

6. The refrigeration cycle apparatus of claim 1 , wherein
the controller brings the relay unit into the open state when an input current input from the direct-current supply device becomes smaller than a reference current set in advance.

7. The refrigeration cycle apparatus of claim 1 , wherein
the controller brings the relay unit into the open state when a difference current calculated by subtracting an input current input from the direct-current supply device from a current input to the DC/AC converter exceeds a threshold current set in advance.

8. The refrigeration cycle apparatus of claim 7 , further comprising
a first current sensor configured to detect the input current input from the direct-current supply device; and
a second current sensor configured to detect the current input to the DC/AC converter, wherein
the controller uses a difference between a value detected by the first current sensor and a value detected by the second current sensor as the difference current.

9. The refrigeration cycle apparatus of claim 7 , further comprising
a difference detecting sensor configured to detect the difference current and wired in such a manner that a current supplied from the direct-current supply device and the current input to the DC/AC converter flow in directions opposite to each other.

10. The refrigeration cycle apparatus of claim 1 , wherein
the controller brings the relay unit into the open state when an output current from the smoothing capacitor exceeds a smoothing reference current set in advance.

11. The refrigeration cycle apparatus of claim 1 , further comprising
an AC/DC converter configured to convert the alternating-current voltage supplied from the alternating-current power supply device into a direct-current voltage, and
the battery being provided on an output side of the AC/DC converter.

Assignees

• Mitsubishi Electric Corp

Inventors

• Iwata Akihiko
• Kawai Kazuhiko
• Kobata Tomoaki
• Koyama Yusuke

Classifications

• H02M5/44

  using discharge tubes or semiconductor devices to convert the intermediate DC into AC · CPC title

• F25B13/00

  Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) · CPC title

• F25B2600/11

  Fan speed control · CPC title

• F25B49/02

  for compression type machines, plants or systems · CPC title

• F25B2700/15

  Power, e.g. by voltage or current · CPC title